Julie,
17 years is a long time to share with a dog. You were very fortunate. Thank you for your condolences -- I send mine to you as well. Rowdy's lung cancer was clearly spread from some other organ, probably liver or spleen, which is why we opted not to operate. It would only have started a process with ultimately the same ending. So, instead, we shared life with him for 3 more months and he gave us joy for 3 more months.
Crash was more sudden but, in some ways, more kind. He had little discomfort and was still a pretty happy boy when we said "goodbye". I wish we had had more time to love on him but we couldn't trade that for increased suffering on his part. Besides, somebody had to warn the dogs at Rainbow Bridge not to mess with the Golden Guy

and Rowdy knew that better than anyone.
Welcome to the forum. I look forward to seeing more of your work.
Jim